php 数组
对于网页编程来说，最重要的就是存取和读写数据了。存储方式可能有很多种，可以是字符串、数组、文件的形式等，今天学习了数组，可以说是PHP的数据应用中较重要的一种方式。PHP的数组函数众多，下面是我学习的小结，借此记之，便于以后鉴之……
一、数组定义：
数组的定义使用 array（）方式定义，可以定义空数组：
.foreach遍历：
<?
php
$number
=
array
(
1
,
3
,
5
,
7
,
9
);
//
定义空数组
$result
=
array
();
$color
=
array
(
"
red
"
,
"
blue
"
,
"
green
"
);
//
自定义键值
$language
=
(
1
=>
"
English
"
,
3
=>
"
Chinese
"
,
5
=>
"
Franch
"
);
//
定义二维数组
$two
=
array
(
"
color
"
=>
array
(
"
red
"
,
"
blue
"
)
,
//
用逗号结尾
"
week
"
=>
array
(
"
Monday
"
,
"
Friday
"
)
//
最后一句没有标点
)；
?>
二、创建数组：
创建数组包含的函数有compact()、
1.compact()函数——将一个或多个变量（包含数组）转换为数组：
array compact ( mixed $varname [, mixed $... ] )
<?
PHP
$number
=
"
1,3,5,7,9
"
;
$string
=
"
I'm PHPer
"
;
$array
=
array
(
"
And
"
,
"
You?
"
);
$newArray
=
compact
(
"
number
"
,
"
string
"
,
"
array
"
);
print_r
(
$newArray
);
?>
compact()函数用于将两个或多个变量转换为数组，当然也包含数组变量。其参数是变量的名称而非带有$全名。
相反的函数是extract()作用顾名思义就是将数组转换为单个的字符串，键值作为其字符串名称，数组值作为字符串的值。
运行结果:
Array (
[
number
]
=
>
1
,
3
,
5
,
7
,
9
[
string
]
=
> I'm PHPer
[
array
]
=
> Array (
[
0
]
=
> And
[
1
]
=
> You? ) )
2.array_combine()——将两个数组重组成一个数组,一个作键值一个做的值：
array array_combine ( array $keys , array $values )
<?
PHP
$number
=
array
(
"
1
"
,
"
3
"
,
"
5
"
,
"
7
"
,
"
9
"
);
$array
=
array
(
"
I
"
,
"
Am
"
,
"
A
"
,
"
PHP
"
,
"
er
"
);
$newArray
=
array_combine
(
$number
,
$array
);
print_r
(
$newArray
);
?>
array_combine函数不多说了，谁看了都明白
运行结果：
Array (
[
1
]
=
> I
[
3
]
=
> Am
[
5
]
=
> A
[
7
]
=
> PHP
[
9
]
=
> er )
3.range()函数——创建指定范围的数组：
不多说了，直接上实例——
<?
PHP
$array1
=
range
(
0
,
100
,
10
);
//
0为起始值，100为结束值，10为步进值(默认步进值为1).
print_r
(
$array1
);
echo
"
<br />
"
;
$array2
=
range
(
"
A
"
,
"
Z
"
);
print_r
(
$array2
);
echo
"
<br />
"
;
$array3
=
range
(
"
z
"
,
"
a
"
);
print_r
(
$array3
);
?>
range()函数的默认步进值是1！
运行结果：
Array
( [
0
]
=>
0
[
1
]
=>
10
[
2
]
=>
20
[
3
]
=>
30
[
4
]
=>
40
[
5
]
=>
50
[
6
]
=>
60
[
7
]
=>
70
[
8
]
=>
80
[
9
]
=>
90
[
10
]
=>
100
)
Array
( [
0
]
=>
A [
1
]
=>
B [
2
]
=>
C [
3
]
=>
D [
4
]
=>
E [
5
]
=>
F [
6
]
=>
G [
7
]
=>
H [
8
]
=>
I [
9
]
=>
J [
10
]
=>
K [
11
]
=>
L [
12
]
=>
M [
13
]
=>
N [
14
]
=>
O [
15
]
=>
P [
16
]
=>
Q [
17
]
=>
R [
18
]
=>
S [
19
]
=>
T [
20
]
=>
U [
21
]
=>
V [
22
]
=>
W [
23
]
=>
X [
24
]
=>
Y [
25
]
=>
Z )
Array
( [
0
]
=>
z [
1
]
=>
y [
2
]
=>
x [
3
]
=>
w [
4
]
=>
v [
5
]
=>
u [
6
]
=>
t [
7
]
=>
s [
8
]
=>
r [
9
]
=>
q [
10
]
=>
p [
11
]
=>
o [
12
]
=>
n [
13
]
=>
m [
14
]
=>
l [
15
]
=>
k [
16
]
=>
j [
17
]
=>
i [
18
]
=>
h [
19
]
=>
g [
20
]
=>
f [
21
]
=>
e [
22
]
=>
d [
23
]
=>
c [
24
]
=>
b [
25
]
=>
a )
4.array_fill()函数——填充数组函数：
<?
PHP
$array
=
range
(
1
,
10
);
$fillarray
=
range
(
"
a
"
,
"
d
"
);
$arrayFilled
=
array_fill
(
0
,
5
,
$fillarray
);
//
这里的$fillarray可以是字符串，如"test".
echo
"
<pre>
"
;
print_r
(
$arrayFilled
);
echo
"
</pre>
"
;
$keys
=
array
(
"
string
"
,
"
2
"
,
9
,
"
SDK
"
,
"
PK
"
);
$array2
=
array_fill_keys(
$keys
,
"
testing
"
);
echo
"
<pre>
"
;
print_r
(
$array2
);
echo
"
</pre>
"
;
?>
运行结果：
Array
( [
0
]
=>
Array
( [
0
]
=>
a [
1
]
=>
b [
2
]
=>
c [
3
]
=>
d ) [
1
]
=>
Array
( [
0
]
=>
a [
1
]
=>
b [
2
]
=>
c [
3
]
=>
d ) [
2
]
=>
Array
( [
0
]
=>
a [
1
]
=>
b [
2
]
=>
c [
3
]
=>
d ) [
3
]
=>
Array
( [
0
]
=>
a [
1
]
=>
b [
2
]
=>
c [
3
]
=>
d ) [
4
]
=>
Array
( [
0
]
=>
a [
1
]
=>
b [
2
]
=>
c [
3
]
=>
d ) )
Array
( [
string
]
=>
testing [
2
]
=>
testing [
9
]
=>
testing [SDK]
=>
testing [PK]
=>
testing )
三、数组的遍历：
1.foreach遍历：
foreach (array_expression as $value){}
foreach (array_expression as $key => $value){}
闲话少说，上实例：
<?
PHP
$speed
=
array
(
50
,
120
,
180
,
240
,
380
);
foreach
(
$speed
as
$keys
=>
$values
){
echo
$keys
.
"
=>
"
.
$values
.
"
<br />
"
; }
?>
运行结果：
0
=>
50
1
=>
120
2
=>
180
3
=>
240
4
=>
380
2.while循环遍历：
while循环遍历一般结合list函数，以下是实例
<?
PHP
$staff
=
array
(
array
(
"
姓名
"
,
"
性别
"
,
"
年龄
"
)
,
array
(
"
小张
"
,
"
男
"
,
24
)
,
array
(
"
小王
"
,
"
女
"
,
25
)
,
array
(
"
小李
"
,
"
男
"
,
23
) );
echo
"
<table border=2>
"
;
while
(
list
(
$keys
,
$value
)
=
each
(
$staff
)){
list
(
$name
,
$sex
,
$age
)
=
$value
;
echo
"
<tr><td>
$name
</td><td>
$sex
</td><td>
$age
</td></tr>
"
; }
echo
"
</table>
"
;
?>
运行结果：
| 姓名 | 性别 | 年龄 |
| 小张 | 男 | 24 |
| 小王 | 女 | 25 |
| 小李 | 男 | 23 |
3.for循环遍历：
<?
PHP
$speed
=
range
(
0
,
220
,
20
);
for
(
$i
=
0
;
$i
<
count
(
$speed
);
$i
++
) {
echo
$speed
[
$i
]
.
"
"
; }
?>
运行结果：
0
20
40
60
80
100
120
140
160
180
200
220
四、数组的指针操作：
涉及函数包括reset、prev、end、next、current、each
实例一：
<?
PHP
$speed
=
range
(
0
,
220
,
20
);
echo
current
(
$speed
);
//
输出当前位置的值（在数组的开头位置）
$i
=
rand
(
1
,
11
);
while
(
$i
--
){
next
(
$speed
);
//
指针从当前位置向后移动一位
}
echo
current
(
$speed
);
//
输出当前位置的值
echo
"
<br />
"
;
echo
prev
(
$speed
);
//
输出前一位置数组值
echo
"
<br />
"
;
echo
reset
(
$speed
);
//
重置数组的指针，将指针指向起始位置
echo
"
<br />
"
;
echo
end
(
$speed
);
//
输出最后位置的数组值
echo
"
<br />
"
;
?>
运行结果：
0220
200
0
220
实例二：each函数指针操作
<?
PHP
$speed
=
range
(
0
,
200
,
40
);
echo
"
each实现指针下移 <br />
"
;
echo
"
0挡的速度是
"
.
current
(
each
(
$speed
))
.
"
<br />
"
;
echo
"
1挡的速度是
"
.
current
(
each
(
$speed
))
.
"
<br />
"
;
echo
"
2挡的速度是
"
.
current
(
each
(
$speed
))
.
"
<br />
"
;
echo
"
3挡的速度是
"
.
current
(
each
(
$speed
))
.
"
<br />
"
;
echo
"
4挡的速度是
"
.
current
(
each
(
$speed
))
.
"
<br />
"
;
echo
"
5挡的速度是
"
.
current
(
each
(
$speed
))
.
"
<br />
"
;
echo
"
使用each函数实现数组指针的移动，进行数组遍历 <br />
"
;
reset
(
$speed
);
//
这里是将数组指针指向数组首
while
(
list
(
$key
,
$value
)
=
each
(
$speed
)){
echo
$key
.
"
=>
"
.
$value
.
"
<br />
"
; }
?>
运行结果：
each实现指针下移 0挡的速度是0 1挡的速度是40 2挡的速度是80 3挡的速度是120 4挡的速度是160 5挡的速度是200 使用each函数实现数组指针的移动，进行数组遍历
0
=>
0
1
=>
40
2
=>
80
3
=>
120
4
=>
160
5
=>
200
五、数组的增添删改操作：
1.增添数组成员：
实例一：$num[] = value直接赋值追加到数组末尾：
<?
PHP
$num
=
array
(
1
=>
80
,
2
=>
120
,
3
=>
160
);
echo
"
使用表达式添加数组成员<br />
"
;
$num
[]
=
240
;
print_r
(
$num
);
?>
使用表达式添加数组成员
Array
( [
0
]
=>
80
[
1
]
=>
120
[
2
]
=>
160
[
3
]
=>
240
)
实例二：array_pad函数，数组数组首尾选择性追加
<?
PHP
$num
=
array
(
1
=>
80
,
2
=>
120
,
3
=>
160
);
$num
=
array_pad
(
$num
,
4
,
200
);
echo
"
使用array_pad函数向数组尾部添加成员<br />
"
;
print_r
(
$num
);
echo
"
<br />array_pad 还可以填充数组首部<br />
"
;
$num
=
array_pad
(
$num
,-
8
,
40
);
print_r
(
$num
);
?>
运行结果：
使用array_pad函数向数组尾部添加成员
Array
( [
0
]
=>
80
[
1
]
=>
120
[
2
]
=>
160
[
3
]
=>
200
)
array_pad
还可以填充数组首部
Array
( [
0
]
=>
40
[
1
]
=>
40
[
2
]
=>
40
[
3
]
=>
40
[
4
]
=>
80
[
5
]
=>
120
[
6
]
=>
160
[
7
]
=>
200
)
实例三：入栈操作追加（array_push）：
<?
PHP
$num
=
array
(
1
=>
80
,
2
=>
120
,
3
=>
160
);
array_push
(
$num
,
200
,
240
,
280
);
//
可以自己追加，直接加在数组结尾
print_r
(
$num
);
?>
运行结果：
Array
( [
1
]
=>
80
[
2
]
=>
120
[
3
]
=>
160
[
4
]
=>
200
[
5
]
=>
240
[
6
]
=>
280
)
实例四：array_unshift()在开头添加数组成员
<?
PHP
$num
=
array
(
1
=>
80
,
2
=>
120
,
3
=>
160
);
array_unshift
(
$num
,
0
,
40
);
//
可以自己追加，直接加在数组结尾
print_r
(
$num
);
?>
运行结果：
Array
( [
0
]
=>
0
[
1
]
=>
40
[
2
]
=>
80
[
3
]
=>
120
[
4
]
=>
160
)
注意：array_unshift()函数使用后数组的键值将会从0开始！
2.删减数组成员：
实例一：unset()命令删除数组成员或数组：
<?
PHP
$num
=
array_fill
(
0
,
5
,
rand
(
1
,
10
));
print_r
(
$num
);
echo
"
<br />
"
;
unset
(
$num
[
4
]);
print_r
(
$num
);
echo
"
<br />
"
;
unset
(
$num
);
if
(
is_array
){
echo
"
unset命令不能删除整个数组
"
; }
else
{
echo
"
unset命令可以删除数组
"
; }
?>
Array
( [
0
]
=>
9
[
1
]
=>
9
[
2
]
=>
9
[
3
]
=>
9
[
4
]
=>
9
)
Array
( [
0
]
=>
9
[
1
]
=>
9
[
2
]
=>
9
[
3
]
=>
9
) Notice
:
Use
of undefined
constant
is_array
-
assumed
'
is_array
'
in H
:
\wamp\www\testing\editorplus\test
.
php on line
21
unset命令不能删除整个数组
实例二：array_splice()函数删除数组成员
<?
php
$a
=
array
(
"
red
"
,
"
green
"
,
"
blue
"
,
"
yellow
"
);
count
(
$a
);
//
得到4
array_splice
(
$a
,
1
,
1
);
//
删除第二个元素
count
(
$a
);
//
得到3
echo
$a
[
2
];
//
得到yellow
echo
$a
[
1
];
//
得到blue
?>
实例三：array_unique删除数组中的重复值：
<?
php
$a
=
array
(
"
red
"
,
"
green
"
,
"
blue
"
,
"
yellow
"
,
"
blue
"
,
"
green
"
);
$result
=
array_unique
(
$a
);
print_r
(
$result
);
?>
运行结果：
Array
( [
0
]
=>
red [
1
]
=>
green [
2
]
=>
blue [
3
]
=>
yellow )
实例四：array_merge、array_merge_recursive合并数组
<?
php
$array1
=
array
(
"
r
"
=>
"
red
"
,
1
,
2
,
3
,
4
);
$array2
=
array
(
"
b
"
=>
"
blue
"
,
4
=>
5
,
6
,
7
,
8
,
9
);
$array3
=
array
(
"
r
"
=>
"
read
"
,
4
=>
10
,
2
=>
11
);
$array4
=
array
(
array
(
4
=>
10
)
,
array
(
7
=>
13
) );
$array5
=
array
(
array
(
4
=>
11
)
,
array
(
6
=>
12
) );
$result
=
array_merge
(
$array1
,
$array2
,
$array3
,
$array4
,
$array5
);
echo
"
<pre>
"
;
print_r
(
$result
);
echo
"
</pre>
"
;
$result
=
array_merge_recursive
(
$array1
,
$array2
,
$array3
,
$array4
,
$array5
);
echo
"
<pre>
"
;
print_r
(
$result
);
echo
"
</pre>
"
;
?>
Array
( [r]
=>
read [
0
]
=>
1
[
1
]
=>
2
[
2
]
=>
3
[
3
]
=>
4
[b]
=>
blue [
4
]
=>
5
[
5
]
=>
6
[
6
]
=>
7
[
7
]
=>
8
[
8
]
=>
9
[
9
]
=>
10
[
10
]
=>
11
[
11
]
=>
Array
( [
4
]
=>
10
) [
12
]
=>
Array
( [
7
]
=>
13
) [
13
]
=>
Array
( [
4
]
=>
11
) [
14
]
=>
Array
( [
6
]
=>
12
) )
Array
( [r]
=> Array ( [0] => red [1] =>
read ) [
0
]
=>
1
[
1
]
=>
2
[
2
]
=>
3
[
3
]
=>
4
[b]
=>
blue [
4
]
=>
5
[
5
]
=>
6
[
6
]
=>
7
[
7
]
=>
8
[
8
]
=>
9
[
9
]
=>
10
[
10
]
=>
11
[
11
]
=>
Array
( [
4
]
=>
10
) [
12
]
=>
Array
( [
7
]
=>
13
) [
13
]
=>
Array
( [
4
]
=>
11
) [
14
]
=>
Array
( [
6
]
=>
12
) )
2.array_merge_recursive函数的作用是将相同字符串的键名单元整合成一个数组。
六、数组的键值和值操作：
实例一：in_array()检测数组中是否有某个值存在
<?
php
$array
=
range
(
0
,
9
);
if
(
in_array
(
9
,
$array
)){
echo
"
数组中存在
"
; }
?>
运行结果：
数组中存在 |
实例二：key()取得数组当前的键名：
<?
php
$array
=
range
(
0
,
9
);
$num
=
rand
(
0
,
8
);
while
(
$num
--
)
next
(
$array
);
$key
=
key
(
$array
);
echo
$key
;
?>
此实例结果为动态结果，范围（0-8），不做结果演示。
实例三：list()函数把数组中的值赋给指定变量：
<?
PHP
$staff
=
array
(
array
(
"
姓名
"
,
"
性别
"
,
"
年龄
"
)
,
array
(
"
小张
"
,
"
男
"
,
24
)
,
array
(
"
小王
"
,
"
女
"
,
25
)
,
array
(
"
小李
"
,
"
男
"
,
23
) );
echo
"
<table border=2>
"
;
while
(
list
(
$keys
,
$value
)
=
each
(
$staff
)){
list
(
$name
,
$sex
,
$age
)
=
$value
;
echo
"
<tr><td>
$name
</td><td>
$sex
</td><td>
$age
</td></tr>
"
; }
echo
"
</table>
"
;
?>
实例四：array_flip()交换数组的键值和值:
<?
PHP
$array
=
array
(
"
red
"
,
"
blue
"
,
"
yellow
"
,
"
Black
"
);
print_r
(
$array
);
echo
"
<br />
"
;
$array
=
array_flip
(
$array
);
print_r
(
$array
);
?>
运行结果：
Array
( [
0
]
=>
red [
1
]
=>
blue [
2
]
=>
yellow [
3
]
=>
Black )
Array
( [red]
=>
0
[blue]
=>
1
[yellow]
=>
2
[Black]
=>
3
)
实例五：array_keys()、array_values()返回数组中所有的键值和值：
<?
PHP
$array
=
array
(
"
red
"
,
"
blue
"
,
"
yellow
"
,
"
Black
"
);
$result
=
array_keys
(
$array
);
print_r
(
$result
);
echo
"
<br />
"
;
$result
=
array_values
(
$array
);
print_r
(
$result
);
?>
运行结果：
Array
( [
0
]
=>
0
[
1
]
=>
1
[
2
]
=>
2
[
3
]
=>
3
)
Array
( [
0
]
=>
red [
1
]
=>
blue [
2
]
=>
yellow [
3
]
=>
Black )
实例六：array_search()搜索数值:
<?
PHP
$array
=
array
(
"
red
"
,
"
blue
"
,
"
yellow
"
,
"
Black
"
);
$result
=
array_search
(
"
red
"
,
$array
);
if
((
$result
===
NULL
)){
echo
"
不存在数值red
"
; }
else
{
echo
"
存在数值
$result
"
; }
?>
结果：存在数值 0
函数array_search()返回的值可能为false或0或NULL，所以在判断时注意要用"==="
七、数组的排序：
实例一：sort()、rsort()/asort()、arsort()对数组排序：
<?
PHP
$array
=
array
(
"
b
"
,
"
c
"
,
"
d
"
,
"
a
"
);
sort
(
$array
);
//
从低到高排序
print_r
(
$array
);
echo
"
<br />
"
;
rsort
(
$array
);
//
逆向排序
print_r
(
$array
);
?>
结果：
Array
( [
0
]
=>
a [
1
]
=>
b [
2
]
=>
c [
3
]
=>
d )
Array
( [
0
]
=>
d [
1
]
=>
c [
2
]
=>
b [
3
]
=>
a )
sort()、rsort()函数对数组进行从低到高的排序，返回结果为bool值；
asort()、arsort()函数是保留键值的排序，排序后键值不重新索引。
实例二：将数组顺序打乱——shuffle()函数：
<?
PHP
$array
=
array
(
"
a
"
,
"
b
"
,
"
c
"
,
"
d
"
);
shuffle
(
$array
);
//
从低到高排序
print_r
(
$array
);
?>
结果为动态结果：
Array
( [
0
]
=>
c [
1
]
=>
a [
2
]
=>
d [
3
]
=>
b )
shuffle的结果有点随机的意味，每次刷新都不一样。
实例三：array_reverse()数组反向：
<?
PHP
$array
=
array
(
"
d
"
,
"
b
"
,
"
a
"
,
"
c
"
);
$array
=
array_reverse
(
$array
);
//
从低到高排序
print_r
(
$array
);
?>
运行结果：
Array
( [
0
]
=>
c [
1
]
=>
a [
2
]
=>
b [
3
]
=>
d )
实例四：自然排序算法——natsort()和natcasesort();
<?
PHP
$array
=
array
(
"
sort2
"
,
"
Sort5
"
,
"
sort1
"
,
"
sort4
"
);
natsort
(
$array
);
//
从低到高排序
print_r
(
$array
);
echo
"
<br />
"
;
natcasesort
(
$array
);
print_r
(
$array
);
?>
结果：
Array
( [
1
]
=>
Sort5 [
2
]
=>
sort1 [
0
]
=>
sort2 [
3
]
=>
sort4 )
Array
( [
2
]
=>
sort1 [
0
]
=>
sort2 [
3
]
=>
sort4 [
1
]
=>
Sort5 )
natsort()、natcasesort()对数组进行自然排序，就是使用数字的正常排序算法。natcasesort会忽略大小写。
实例五：对数组进行键值排序ksort():
<?
PHP
$array
=
array
(
1
=>
"
sort2
"
,
4
=>
"
Sort5
"
,
2
=>
"
sort1
"
,
3
=>
"
sort4
"
);
ksort
(
$array
);
//
从低到高排序
print_r
(
$array
);
?>
结果：
Array
( [
1
]
=>
sort2 [
2
]
=>
sort1 [
3
]
=>
sort4 [
4
]
=>
Sort5 )
注意：ksort()函数重新建立了索引。
八、数组的其他用法：
cout($array) --------统计数组的单元个数
array_diff($array1,$array2)----------统计数组之间的不同点，返回第一个数组中有而第二个数组中没有的。
array_diff_assoc($array1,$array2)---------同array_diff()，只是它对键值也比较
array_diff_key($array1,$array2)------------比较键值
array_product($array)-----------返回数组的所有数的乘积
array_sum($array)--------------所有数值的和
array_rand($array,$n)----------在$array数组中取出$n个数值，返回数组
array_intersect($array1,$array2)----------------取得两个数组的交集
array_intersect_assoc($array1,$array2)---------------在array_intersect 的基础上进行键值比较
array_intersect_key($array1,$array2)-----------------比较两个数组键值的交集
总结：
数组的使用在PHP中至关重要，由于PHP没有指针，所以数组承担了很大的数据操作任务。学好数组，才能把PHP应用的得心应手，这里所列均是常用的PHP数组相关的函数及用法，欢迎一起学习！